Thanks @jkatz1488 and @Sami ! I guess this leads me to another question, is "not" a part of group 4? I put that down in my notes early on but now I'm second guessing that.
ahh thank you Sami your second explanation helped too I finally get it, I appreciate it!!! now if only I could understand the other one visually with respect to floaters!
Oh absolutely. Nothing can beat the real thing; but for times when you want some down time, I figured some other puzzles or reading would come more handy than my Facebook app lol! Thanks for your input :)